Now available, just in time for Lent: Triodion Prokeimena (http://www.lulu.com/shop/rdr-peter-gardner/triodion-prokeimena/paperback/product-22019547.html)
This book contains musical settings for the prokeimena from the Lenten Triodion, in accordance with the Lenten Lectionary and Prophetologion from the same publisher. The text is consistent with the Russian tradition, and the melodies are those in common use in the Russian Church.
The majority of the settings are unison; parts are only given for prokeimena at Vespers on Holy Thursday, Friday, and Saturday. The refrains from the Old Testament readings on Holy Saturday are also included.